Market forces are the main determinant of this, with the old supply and demand factors pulling and pushing from their respective corners, but the web adds a little twist.

各个市场产品的投放和消耗，供应与需求，使市场的力量成为价格的主要决定因素，但是网络略有不同。

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But if we are focusing purely on the business cycle, then shocks to the supply and demand for money (including expectations of future changes) are the primary determinant of the pace of recovery.

但是如果我们只是单纯地把注意力放在商业周期上，那么货币供求的震动(包括对货币未来变化的期望)就是决定经济复苏速度的主导因素。

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"The main determinant to commodities is supply and demand, " said Mr Rodgers.

BBC: How China drives commodities down

Assuming demand holds up of course: and there the big determinant is the urbanisation of China.

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